It has long been desirable to have a removable auxiliary lens assembly attached to eyeglasses. Professional baseball players have used “flip-up” auxiliary lenses for more than four decades to protect their eyes from the sun, but to allow them unrestricted vision in the event the ball was hit in their vicinity without the necessity of removing the auxiliary lens assembly from the primary assembly altogether.
Various means have been provided for attaching flip-up or hinged auxiliary lenses to a primary lens assembly. Typically, the means of attachment between the primary and auxiliary lens assembly is either complex and difficult and expensive to manufacture, or flimsy (and easily manufactured). A need exists, therefore, for improved means for attachment of hinged auxiliary lens assemblies to primary lens assemblies that is both robust in its attachment, yet easily manufactured.